wininet.InternetOpenUrlA ERROR_SXS_ACTIVATION_CONTEXT_DISABLED - windows

Question

I have this program:
#include <string>
#include <iostream>
#include <fstream>
#include <windows.h>
#include <wininet.h>
#include <winsock.h>
#include <stdio.h>
#include <stdarg.h>
using namespace std;
int main()
{
HINTERNET hOpen, hURL;
LPCTSTR NameProgram = "UA"; // LPCWSTR == Long Pointer to Const Wide String
LPCTSTR Website;
char file[101];
unsigned long read;
//Always need to establish the internet connection with this funcion.
if ( !(hOpen = InternetOpen(NameProgram, INTERNET_OPEN_TYPE_DIRECT, NULL, NULL, 0 )))
{
cerr << "Error in opening internet" << endl;
return 0;
}
Website = "www.c-jump.com";
hURL = InternetOpenUrl( hOpen, Website, NULL, 0, 0, 0 ); //Need to open the URL
InternetReadFile(hURL, file, 100, &read);
while (read == 100)
{
InternetReadFile(hURL, file, 100, &read);
file[read] = '\0';
cout << file;
}
cout << endl;
InternetCloseHandle(hURL);
return 0;
}
which I've compiled like this:
C:\Users\user\Desktop>cl.exe new.cpp /link "wininet.lib"
Microsoft (R) C/C++ Optimizing Compiler Version 19.10.25019 for x86
Copyright (C) Microsoft Corporation. All rights reserved.
new.cpp
C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Tools\MSVC\14.10.25017\include\xlocale(314): warning C4530: C++ exception handler used, but unwind semantics are not enabled. Specify /EHsc
C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Tools\MSVC\14.10.25017\include\exception(366): warning C4577: 'noexcept' used with no exception handling mode specified; termination on exception is not guaranteed. Specify /EHsc
Microsoft (R) Incremental Linker Version 14.10.25019.0
Copyright (C) Microsoft Corporation. All rights reserved.
/out:new.exe
wininet.lib
new.obj
I run the exe and get no output, I'm expecting the HTML response from the URL to be printed to stdout. I run the code in a debugger and get the following error returned when the InternetOpenUrlA function returns:
ERROR_SXS_ACTIVATION_CONTEXT_DISABLED (00002EE6)
I'm running Windows on Windows 10.
Could anyone shed any light on what this means and how one could resolve the issue? I had the same code working earlier yesterday and then suddenly it stopped working, with some Windows updates getting installed in between.
Many many thanks
Charlie

Answer 1

The error is probably ERROR_INTERNET_UNRECOGNIZED_SCHEME because your URL does not have a scheme/protocol. Just fix the URL: Website = "http://www.c-jump.com"; Your read loop also has issues, you throw away the first 100 bytes! There is also no guarantee that it can read 100 bytes each time.
You can also attempt to fix the URL:
DWORD DumpResponse(const char *URL)
{
LPCSTR agent = "Stackoverflow Example";
DWORD error, read;
HINTERNET hInet, hConn;
char data[101], urlbuf[INTERNET_MAX_URL_LENGTH];
const char *defscheme = "http";
URL_COMPONENTSA uc;
ZeroMemory(&uc, sizeof(uc));
uc.dwStructSize = sizeof(uc);
BOOL crack = InternetCrackUrlA(URL, 0, 0, &uc);
error = GetLastError();
printf("DBG: InternetCrackUrlA error %d\n", crack ? 0 : error);
if (!crack && error == ERROR_INTERNET_UNRECOGNIZED_SCHEME && strlen(defscheme) + 3 + strlen(URL) < INTERNET_MAX_URL_LENGTH)
{
// Prepend a protocol
sprintf(urlbuf, "%s://%s", defscheme, URL);
URL = urlbuf;
}
else if (!crack)
{
return error;
}
hInet = InternetOpenA(agent, INTERNET_OPEN_TYPE_DIRECT, NULL, NULL, 0);
if (!hInet) return GetLastError();
hConn = InternetOpenUrlA(hInet, URL, NULL, 0, 0, 0);
error = GetLastError();
if (!hConn)
{
InternetCloseHandle(hInet);
printf("DBG: InternetOpenUrl failed with error %d\n", error);
return error;
}
error = 0;
for (;;)
{
if (!InternetReadFile(hConn, data, sizeof(data) - 1, &read))
{
error = GetLastError();
break;
}
if (0 == read) break; // Done
data[read] = '\0';
printf("%s", data);
}
InternetCloseHandle(hInet);
InternetCloseHandle(hConn);
return error;
}
int main()
{
printf("----\nDumpResponse returned %d\n", DumpResponse("www.c-jump.com"));
}